The following miscellaneous observations on Japanese tactics on Guadalcanal were made
by a U.S. Marine colonel, commander of one of the Marine regiments.
* * *
The Jap has been taught that he is invincible. He is accustomed to having the enemy run when
Japanese elements get around their enemy's flanks and rear. He is also accustomed to the
enemy running when he charges with the bayonet. In his night attacks, he expects the enemy
to be caught in front of or on the tactical objective (always an identifiable terrain or
other feature) and to be defeated; thus, the mission of his night operations is accomplished.
Consequently he has been upset, confused, and defeated by American troops who do not run, who
themselves charge with the bayonet, and who are not where they are expected to be in night
attacks--instead, they counterattack when the Japanese are confused and in process of
reorganizing after having reached their night-attack objective.
In night attacks the Japanese would send advance parties by the valleys through the denser
cover, reserving the more open terrain of the higher ground for the main body and main
effort. They would have the main body make considerable noise in order to drown out any noise
the advance parties might make. The Jap has had the advance parties clear away jungle growth
along avenues of subsequent approach for larger units, and has "blazed" the trails thus
cleared with luminous paint. The Jap moves his main forces up in closed-up columns--partly
for reasons of command control.
For purposes of control and orientation, Japanese night attacks followed clearly defined terrain
features, e.g., a crest ridge-line or a stream. The Japanese selected night-attack objectives
from observation of our dispositions at sunset. If he later fails to find these dispositions
where he expects them, he becomes confused in the dark and does not know where to look for
us. It would take him an hour or two to get reorganized, and that was the time to counterattack
him. Heavy casualties were inflicted on him then.
On Tulagi, the Jap took up his positions on the reverse slopes. This gave him better visibility
up against the crests and sky, and permitted intense surprise fire of devastating effect at short
ranges. However, when he counterattacked at night out of these positions, he suffered so many
casualties that he did not have men enough to hold his reverse-slope positions the next day.
The Japanese machine-gun dugouts were held in strengths of 10 to 12 men. When one man was
killed, another stepped up and manned the gun. This required every man to be killed, and so
the positions held out for hours. Immediately after the Jap discovers a machine gun, he will send
over mortar bombs, usually within 10 minutes. The Jap digs in wherever he stops. In a few
minutes he will have a slit trench, and in 20 minutes a man-deep foxhole.